Using a Zeroplus Logic Cube I'm tapping into an 8bit one direction bus that has a 20Mhz clock. Since the Logic Cube can not be driven synchronously with the clock, I wanted to capture it's pulses for reference.
Problem is I see missing or erroneous samples no matter what trigger, sample rate, or voltage level I set the Logic Cube to.
The inputs should all be running between 0v and 5v (Vcc) according to the specifications of the chip being fed.
I've used two scopes (a DSO and Analog scope) and I see a stable clock pulse but it is 2v total with the upper 1v being a triangle wave (see attachment). It isn't square or near square as I had expected.
The circuit is still operating normally with the probes connected.
I'm tempted to put a pulldown resistor on this but afraid of damaging something or causing the circuit to not work correctly.
Anyone familiar with this scenario and how to get this signal in a useful way to look at with a logic analyzer?
I have a few 4050B hex buffers but looks like without the proper logic levels they won't be much help either.
Note: Yellow Marker on the left in this screen shot is at GND
Problem is I see missing or erroneous samples no matter what trigger, sample rate, or voltage level I set the Logic Cube to.
The inputs should all be running between 0v and 5v (Vcc) according to the specifications of the chip being fed.
I've used two scopes (a DSO and Analog scope) and I see a stable clock pulse but it is 2v total with the upper 1v being a triangle wave (see attachment). It isn't square or near square as I had expected.
The circuit is still operating normally with the probes connected.
I'm tempted to put a pulldown resistor on this but afraid of damaging something or causing the circuit to not work correctly.
Anyone familiar with this scenario and how to get this signal in a useful way to look at with a logic analyzer?
I have a few 4050B hex buffers but looks like without the proper logic levels they won't be much help either.
Note: Yellow Marker on the left in this screen shot is at GND
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